United need more than Juan Mata to turn around their season.Alastair Grant/Associated Press

What was shaping up as a relatively quiet January transfer window for Manchester United has exploded with the £37 million move for erstwhile Chelsea midfielder Juan Mata. Mata's arrival signals a push by United to reverse what has been a severely disappointing campaign, as embattled boss David Moyes has promised more moves:

Old Trafford has been salivating at the possibility of a Mata-Wayne Rooney-Robin van Persie attacking triumvirate. Mata adds world-class skill to the midfield position, and the 25-year-old has expressed his happiness at transferring to the Premier League's most storied club:

But while Mata and United are happily basking in their honeymoon period, the Premier League season rolls on, and the Red Devils still have plenty of ground to make up. A repeat championship would be miraculous at this point, so United's primary goal is to erase the six-point gap between themselves and Liverpool for a top-four finish and a Champions League berth.

At this point, that is likely less than a 50-50 proposition for United. In fairness, Mata was almost a necessary move after injuries to Rooney and van Persie fostered a humiliating loss to Sunderland in the Capital One Cup semis. Nevertheless, such a move implies panic from a club desperately trying to cling to its accustomed top-four status, as BBCSport.com's Phil McNulty hints:

There has been loose talk of United being able to take one season on the outside looking in at the Champions League on the chin. This is a dangerous assumption as once you are out there is no guarantee you will get back in.

Liverpool probably thought they would only be absent for one season after failing in 2010 but they have yet to return, and Mata's arrival will be designed to ensure United avoid that fate.

Panic is too strong a word but there is certainly surprise at the speed of United's move and the position they have decided is the priority for such heavy spending.

The price is not the main concern here; United's deep pockets can afford the young midfielder, and the suggestion of future moves from Moyes confirms as much. Indeed, if pure financials were the only concern, there would be no real reason to fret the Mata move.

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However, it is not a given that Mata will transition seamlessly into United's plans, especially in the scope of the second half of the Premier League season.

The Red Devils needed a world-class central midfielder to goose their inability to penetrate the defense from the middle of the field. Mata does fit that No. 10 prototype, but at the moment, there is a logjam up front that will likely require some tactical renovations, per Amit Singh of ThinkFootball.co.uk:

Manchester United genuinely speaking operate in a 4-4-2 under David Moyes or in a 4-4-1-1 formation. Against Chelsea this took the form of Adnan Januzaj playing in behind Danny Welbeck, previously we’ve seen Wayne Rooney playing just behind Robin van Persie. With all players fully fit, van Persie and Rooney are United’s best players, so it appears odd to unsettle this by signing Mata to then compete with Rooney for the No. 10 role.

The players could be rotated, but if Mata left Chelsea one would imagine that he’d do this for a regular starting place, rather than to be involved in squad rotation. Wayne Rooney does have one year left on his contract as of this summer, so potentially Mata could, be a long term replacement for Rooney, but then, surely it would make more sense for United to move for Mata in the summer, rather than immediately. From a tactical stand point it is difficult to see where Mata can fit in.

Tactical analyses are divided on Mata's potential fit, and with good reason. It's very hard to imagine Mata's skill not blending in well with a system that gives him more free reign to create, but at least one former United star believes the Spaniard is a bad fit:

Moreover, even if Mata fits in well and spurs an offensive uptick, he alone cannot solve all of Man United's woes. The Red Devils' defense looks like the team's weakest unit, as the Chelsea loss exposed, and the squad could also use help out wide. Mata may plug one hole if Moyes utilizes him properly, but the Old Trafford dam is still leaking rapidly.

Indeed, the issue is not so much whether or not Mata will improve United (he likely will, it is a question of how much), but the deficit United faces. Besides Liverpool, steady Everton and Tottenham squads sit ahead of United. With only 16 games left in the season, United must hope for slumps from three separate clubs to leapfrog the trio.

The schedule is not too imposing, as just seven games are against the top half of the table, including home matches against Man City and Liverpool. Still, while future transfers may continue to increase United's odds of squeezing into the top four, Juan Mata's arrival alone does not save the underachieving squad.